Penis Extender Question

I am doing now 4 months with the extender,I started on 9 cm because I measure only 13 cm.
I have done now 400 hours in this extender tool and I still measure 13 cm ,the tool is now on 15,5 cm.
My Question is now is this normal that I don’t win anything so far,I use the tool mostly for 1 hour a session ,and sometimes hours sessions in a stage when I change the tool from distance after 10 days or so.
Another Question is how far can you go with this tool if you stay on 13 cm,I first did not think I will ever go over 15 but now I am over it.My dick also measure the same like the extender after I did a couple of hours in the tool,but a day later it still 13 cm.

What am I doing wrong or does the extender not work for me,I only use the extender

From the little experiences I’ve had with these sort of devices, it takes a lot of hours before seeing any
Difference and I don’t think even 400 would be enough to see visible gains but it is
Different for everyone, check out the post 1000 hours on extender or something like that

When I used the device I found the best stretch was somewhere that felt comfortable, you don’t want
To stress your little fellow, it’s meant to be a light constant stretch if for you over 15cm gives you a very strong stretch I would back down a bit ,

Try using the extender at a lower notch 14,5 cm maybe and perhaps for a little longer than an hour per session
I found 90 minute sessions to 120 minute sessions worked best for me but it may not for you, hope some of this helped